Curvaton Potential Terms, Scale-Dependent Perturbation Spectra and Chaotic Initial Conditions

Abstract

The curvaton scenario predicts an almost scale-invariant spectrum of perturbations in most inflation models. We consider the possibility that renormalisable phi^4 or Planck scale-suppressed non-renormalisable curvaton potential terms may result in an observable deviation from scale-invariance. We show that if the curvaton initially has a large amplitude and if the total number of e-foldings of inflation is less than about 300 then a running blue perturbation spectrum with an observable deviation from scale-invariance is likely. D-term inflation is considered as an example with a potentially low total number of e-foldings of inflation. A secondary role for the curvaton, in which it drives a period of chaotic inflation leading to D-term or other flat potential inflation from an initially chaotic state, is suggested.

12 pages LaTeX, minor corrections, to be published in JCAP

References in corpus (2)

• The Curvaton as a Pseudo-Nambu-Goldstone Boson
• Cosmic String from D-term Inflation and Curvaton

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